We do a rust blue on a gun. I am sure I can do more than one gun if I choose to do so. I will check out some more of the matte bluing from other guys that are doing it right now. I looked it up on google images and it had a slightly different color than I saw at school.
I like the name and the slogan for the business venture. I don't think anyone could turn down a business with the name or slogan that show so much care and customer satisfaction.
Probably you are right about the slogan, it could make us gazillionares (no doubt).
I repeat myself by saying "rust blue is the gun metal finish of The Gods"
The ones I have are somewhere around such very dark charcoal color that in other than bright daylight, they look black but not as flat as bead blasted/hot tanked is and nowhere as shiny as high polish blue either.
With the word "rust" in it, one would think such a finish would be at risk in wet weather but I am happy to report that, it resists oxidation better than regular bluing by a noticeable margin.
But no doubt in your schooling, you already know more about that subject than most of us ever will.
Again, I am envious that you are able to build proper Mausers.
Alas, most of us have to pay someone else to build them for us.